Table Of Contents

Read Status (G Dataflow)

Version:
Last Modified: September 16, 2017

Returns measurement backlog and acquisition status.

Use this node to determine how many measurements are available before running Fetch, Fetch Multi Point or Fetch Waveform.

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session in

Instrument identifier from previous NI-DMM nodes.

Default: None

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error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

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session out

Instrument identifier for subsequent NI-DMM nodes.

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backlog

Number of measurements available to be read.

If the backlog continually increases, data is eventually overwritten, resulting in an error.

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acquisition state

Status of the acquisition.

The following table describes the possible values of this parameter.

Value Meaning
0 Acquisition is running.
1 Acquisition finished with a Backlog.
2 Acquisition finished with no Backlog.
3 Acquisition paused.
4 No acquisition in progress.
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error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Where This Node Can Run:

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application

Hardware Support:

Due to the Auto Range model of the PXI/PCI/PCIe/USB-4065, the Backlog does not increase in the following situations:

  • When the Range property is set to AUTO RANGE ON (-1)
  • Before the first point is fetched when the Range property is set to AUTO RANGE ONCE (-3).


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